I have gotten a thrift store find of a steam milk frother that would work on the stove top. It is well made, but I cannot find any directions on the net. Has anyone ever used one. My question is how much water to put in and how long to I let it build the steam, after it comes to a boil. I'm assuming you leave the valve open until the steam is coming out and then shut it down, like you do an old style pressure cooker. It's the same genre as the stove top Italian espresso maker, of which I have a couple sizes. Anyone got some advice for me? Thanks.